Arbovirus Antibody Panel, IgG and IgM (Sendout)

General Information

Lab Name

Lab Code

646

External Test Id

ABOPC, ARBOP

Description

Useful For: Aiding the diagnosis of arboviral encephalitis. Includes IgG and IgM antibody testing for the following:

  • California Virus (LaCrosse) encephalitis
  • St. Louis encephalitis
  • Eastern equine encephalitis
  • Western equine encephalitis

Testing Algorithm:

Synonyms

ABOPC, ARBOP, California (Lacrosse) Virus, Eastern Equine Encephalitis (EEE), St Louis Encephalitis (SLE), VSSLE, VSWEE, Western Equine Encephalitis (WEE)

Interpretation

Method

Immunofluorescence Assay (IFA)

Ref. Range Notes

Reference Values:

Test: IgG: IgM:
California Virus (La Crosse): <1:10 <1:10
Eastern Equine Encephalitis: <1:10 <1:10
St. Louis Encephalitis: <1:10 <1:10
Western Equine Encephalitis: <1:10 <1:10

Interpretation:

In patients infected with these or related viruses, IgM class antibody is reliably detected within 1 to 3 weeks of onset, peaking and rapidly declining within 3 months. Results from a single serum specimen can differentiate early (acute) infection from past infection with immunity if IgM is positive (suggests acute infection).

IgG antibody is generally detectable within 1 to 3 weeks of onset, peaking within 1 to 2 months, and declining slowly thereafter. A single serum specimen IgG of 1:10 or greater indicates exposure to the virus. A 4-fold or greater rise in IgG antibody titer in acute and convalescent sera indicates recent infection.

In the United States, it is unusual for any patient to show positive reactions to more than 1 of the arboviral antigens, although Western equine encephalitis and Eastern equine encephalitis antigens will show a noticeable cross-reactivity.

Interferences and Limitations

Cautions:

All results must be correlated with clinical history and other data available to the attending physician.

Since cross-reactivity with dengue fever virus does occur with St. Louis encephalitis antigens, and, therefore, cannot be differentiated further, the specific virus responsible for positive results may be deduced by the travel history of the patient, along with available medical and epidemiological data, unless the virus can be isolated.

Eastern and Western equine encephalitis viruses show some cross-reactivity; however, antibody response to the infecting virus is typically at least 8-fold higher.

CSF: False-positive results may be caused by breakdown of the blood-brain barrier, or by the introduction of blood into the cerebrospinal fluid (CSF) at collection.

Serum: Specimens collected within the first 2 weeks after onset are variably negative for IgG antibody and should not be used to exclude the diagnosis of arboviral disease. If arboviral infection is suspected, a second specimen should be collected and tested 10 to 21 days later.

Guidelines

Ordering & Collection

Specimen Type

Blood, CSF

Collection

Blood: Collect 3 mL blood in RED TOP tube or GOLD SST.

CSF: Collect 0.7 mL CSF in a sterile vial.

Handling Instructions

Outside Laboratories:

  • CSF: Collect 0.7 mL CSF in a sterile vial. Refrigerate CSF.
  • Blood: Centrifuge sample and transfer serum to a separate plastic vial. Refrigerate serum.

Stability: Refrigerated (preferred): 14 days; Frozen: 14 days; Ambient: Unacceptable.

Reject Due To (Serum Only): Gross hemolysis, gross lipemia.

Quantity

requested: 0.5 mL serum/0.7 mL CSF
minimum: 0.2 mL serum/0.7 mL CSF

Processing

  • Blood: Centrifuge sample and transfer serum to a separate plastic vial. Refrigerate serum.
  • CSF: Refrigerate CSF.

Login: SEND1-;REFRIG

  • RSNDT1: MAYOSD
  • RSTYP1: SRM or CSF
  • RTSRQ1: [Select test below]
    • ;Arbovirus Ab Panel, IgG & IgM, Serum (Mayo Test ARBOP)
    • ;Arbovirus Ab Panel, IgG & IgM, CSF (Mayo Test ABOPC)

Sendouts: Order appropriate Mayo test based on sample type received.

  • Serum: Order ARBOP.
  • CSF: Order ABOPC.

Stability: Refrigerated (preferred): 14 days; Frozen: 14 days; Ambient: Unacceptable.

Reject Due To (Serum Only): Gross hemolysis, gross lipemia.

Performance

LIS Dept Code

Performing Location(s)

Sendout Mayo Clinic Laboratories (Superior Drive)
800-533-1710

3050 Superior Drive NW
Rochester, MN 55901

Frequency

May through Oct: Mon - Fri; 9 a.m. Nov through Apr: Mon, Wed, Fri; 9 a.m. Report Available: 1-4 days.

Available STAT?

No

Billing & Coding

CPT codes

Billing Comments

CPTs:

  • 86651(x2) - California virus (La Crosse) encephalitis antibody, IgG and IgM
  • 86652(x2) - Eastern equine encephalitis antibody, IgG and IgM
  • 86653(x2) - St. Louis encephalitis antibody, IgG and IgM
  • 86654(x2) - Western equine encephalitis antibody, IgG and IgM

LOINC